With the advances of times, the illumination means evolve from light sources for emitting light through article burning, such as a torch, an oil lamp, and a candle, to light sources for emitting light through being energized, such as an incandescent bulb, a fluorescent tube, an energy saving bulb, and a light emitting diode. Because a light emitting device of the light emitting diode has a small volume and lower power consumption, currently many relevant practitioners devote themselves into the development of the relevant field.
In a light emitting device with a light emitting diode, semiconductor layers of different types of a light emitting chip are energized such that a light emitting junction between the semiconductor layers of different types emit light. The light emitted by the light emitting junction can be radiated in various directions, but a user usually uses light emitted by the light emitting chip in front of the light emitting device. Thus, front light output efficiency is often discussed when light output efficiency of a light emitting device is evaluated. Because of light diffraction or the ambient environment of the light emitting chip, light may also be emitted from the light emitting junction from a lateral of the light emitting chip and may possibly contribute to the front light output efficiency of the light emitting device to a certain extent.
However, when electrodes are configured to be electrically connected to the light emitting chip and energize the light emitting chip, the electrodes cover the lateral of the light emitting chip so that a partial range of the lateral of the light emitting chip for emitting light is shielded by the electrodes, thereby reducing the front light output efficiency of the light emitting device.